Xue Sheng
All weight is underside
so why not learn the taiji-appropriate stances thru training taiji? Why can that information not be part of the regular taiji training, instead of needing to learn other stances (that you recognize as not being the same) thru training the rest of the curriculum? It's inconsistent and can develop habits that are bad for taiji and need to be un-learned in order to progress in taiji. This is what we keep saying, that each system has its own foundation and fundamentals on which it is designed to function, and learning a different foundation and then doing taiji, it just doesn't make sense to approach it that way. Would you train Wing Chun as a prep for taiji? Wing Chun's stance is very different, it's an extreme example, but it would be a waste to go that route if taiji was your real goal. Same with SD.
I have seen this with two guys who were trying to learn from my Yang sifu, they both were trying real hard but they could not get the proper stance. One was from uechi ryu and he did finally relax but the stance was still difficult for him. The other was form TKD and Karate and his was always stiff in all movement and he never did get the stance or the movement. He was really trying buy I think he got frustrated and stop coming to class